xref: /openbmc/linux/drivers/gpu/drm/bridge/tc358768.c (revision da1d9caf)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  *  Copyright (C) 2020 Texas Instruments Incorporated - https://www.ti.com
4  *  Author: Peter Ujfalusi <peter.ujfalusi@ti.com>
5  */
6 
7 #include <linux/clk.h>
8 #include <linux/device.h>
9 #include <linux/gpio/consumer.h>
10 #include <linux/i2c.h>
11 #include <linux/kernel.h>
12 #include <linux/module.h>
13 #include <linux/regmap.h>
14 #include <linux/regulator/consumer.h>
15 #include <linux/slab.h>
16 
17 #include <drm/drm_atomic_helper.h>
18 #include <drm/drm_crtc_helper.h>
19 #include <drm/drm_drv.h>
20 #include <drm/drm_mipi_dsi.h>
21 #include <drm/drm_of.h>
22 #include <drm/drm_panel.h>
23 #include <video/mipi_display.h>
24 #include <video/videomode.h>
25 
26 /* Global (16-bit addressable) */
27 #define TC358768_CHIPID			0x0000
28 #define TC358768_SYSCTL			0x0002
29 #define TC358768_CONFCTL		0x0004
30 #define TC358768_VSDLY			0x0006
31 #define TC358768_DATAFMT		0x0008
32 #define TC358768_GPIOEN			0x000E
33 #define TC358768_GPIODIR		0x0010
34 #define TC358768_GPIOIN			0x0012
35 #define TC358768_GPIOOUT		0x0014
36 #define TC358768_PLLCTL0		0x0016
37 #define TC358768_PLLCTL1		0x0018
38 #define TC358768_CMDBYTE		0x0022
39 #define TC358768_PP_MISC		0x0032
40 #define TC358768_DSITX_DT		0x0050
41 #define TC358768_FIFOSTATUS		0x00F8
42 
43 /* Debug (16-bit addressable) */
44 #define TC358768_VBUFCTRL		0x00E0
45 #define TC358768_DBG_WIDTH		0x00E2
46 #define TC358768_DBG_VBLANK		0x00E4
47 #define TC358768_DBG_DATA		0x00E8
48 
49 /* TX PHY (32-bit addressable) */
50 #define TC358768_CLW_DPHYCONTTX		0x0100
51 #define TC358768_D0W_DPHYCONTTX		0x0104
52 #define TC358768_D1W_DPHYCONTTX		0x0108
53 #define TC358768_D2W_DPHYCONTTX		0x010C
54 #define TC358768_D3W_DPHYCONTTX		0x0110
55 #define TC358768_CLW_CNTRL		0x0140
56 #define TC358768_D0W_CNTRL		0x0144
57 #define TC358768_D1W_CNTRL		0x0148
58 #define TC358768_D2W_CNTRL		0x014C
59 #define TC358768_D3W_CNTRL		0x0150
60 
61 /* TX PPI (32-bit addressable) */
62 #define TC358768_STARTCNTRL		0x0204
63 #define TC358768_DSITXSTATUS		0x0208
64 #define TC358768_LINEINITCNT		0x0210
65 #define TC358768_LPTXTIMECNT		0x0214
66 #define TC358768_TCLK_HEADERCNT		0x0218
67 #define TC358768_TCLK_TRAILCNT		0x021C
68 #define TC358768_THS_HEADERCNT		0x0220
69 #define TC358768_TWAKEUP		0x0224
70 #define TC358768_TCLK_POSTCNT		0x0228
71 #define TC358768_THS_TRAILCNT		0x022C
72 #define TC358768_HSTXVREGCNT		0x0230
73 #define TC358768_HSTXVREGEN		0x0234
74 #define TC358768_TXOPTIONCNTRL		0x0238
75 #define TC358768_BTACNTRL1		0x023C
76 
77 /* TX CTRL (32-bit addressable) */
78 #define TC358768_DSI_CONTROL		0x040C
79 #define TC358768_DSI_STATUS		0x0410
80 #define TC358768_DSI_INT		0x0414
81 #define TC358768_DSI_INT_ENA		0x0418
82 #define TC358768_DSICMD_RDFIFO		0x0430
83 #define TC358768_DSI_ACKERR		0x0434
84 #define TC358768_DSI_ACKERR_INTENA	0x0438
85 #define TC358768_DSI_ACKERR_HALT	0x043c
86 #define TC358768_DSI_RXERR		0x0440
87 #define TC358768_DSI_RXERR_INTENA	0x0444
88 #define TC358768_DSI_RXERR_HALT		0x0448
89 #define TC358768_DSI_ERR		0x044C
90 #define TC358768_DSI_ERR_INTENA		0x0450
91 #define TC358768_DSI_ERR_HALT		0x0454
92 #define TC358768_DSI_CONFW		0x0500
93 #define TC358768_DSI_LPCMD		0x0500
94 #define TC358768_DSI_RESET		0x0504
95 #define TC358768_DSI_INT_CLR		0x050C
96 #define TC358768_DSI_START		0x0518
97 
98 /* DSITX CTRL (16-bit addressable) */
99 #define TC358768_DSICMD_TX		0x0600
100 #define TC358768_DSICMD_TYPE		0x0602
101 #define TC358768_DSICMD_WC		0x0604
102 #define TC358768_DSICMD_WD0		0x0610
103 #define TC358768_DSICMD_WD1		0x0612
104 #define TC358768_DSICMD_WD2		0x0614
105 #define TC358768_DSICMD_WD3		0x0616
106 #define TC358768_DSI_EVENT		0x0620
107 #define TC358768_DSI_VSW		0x0622
108 #define TC358768_DSI_VBPR		0x0624
109 #define TC358768_DSI_VACT		0x0626
110 #define TC358768_DSI_HSW		0x0628
111 #define TC358768_DSI_HBPR		0x062A
112 #define TC358768_DSI_HACT		0x062C
113 
114 /* TC358768_DSI_CONTROL (0x040C) register */
115 #define TC358768_DSI_CONTROL_DIS_MODE	BIT(15)
116 #define TC358768_DSI_CONTROL_TXMD	BIT(7)
117 #define TC358768_DSI_CONTROL_HSCKMD	BIT(5)
118 #define TC358768_DSI_CONTROL_EOTDIS	BIT(0)
119 
120 /* TC358768_DSI_CONFW (0x0500) register */
121 #define TC358768_DSI_CONFW_MODE_SET	(5 << 29)
122 #define TC358768_DSI_CONFW_MODE_CLR	(6 << 29)
123 #define TC358768_DSI_CONFW_ADDR_DSI_CONTROL	(0x3 << 24)
124 
125 static const char * const tc358768_supplies[] = {
126 	"vddc", "vddmipi", "vddio"
127 };
128 
129 struct tc358768_dsi_output {
130 	struct mipi_dsi_device *dev;
131 	struct drm_panel *panel;
132 	struct drm_bridge *bridge;
133 };
134 
135 struct tc358768_priv {
136 	struct device *dev;
137 	struct regmap *regmap;
138 	struct gpio_desc *reset_gpio;
139 	struct regulator_bulk_data supplies[ARRAY_SIZE(tc358768_supplies)];
140 	struct clk *refclk;
141 	int enabled;
142 	int error;
143 
144 	struct mipi_dsi_host dsi_host;
145 	struct drm_bridge bridge;
146 	struct tc358768_dsi_output output;
147 
148 	u32 pd_lines; /* number of Parallel Port Input Data Lines */
149 	u32 dsi_lanes; /* number of DSI Lanes */
150 
151 	/* Parameters for PLL programming */
152 	u32 fbd;	/* PLL feedback divider */
153 	u32 prd;	/* PLL input divider */
154 	u32 frs;	/* PLL Freqency range for HSCK (post divider) */
155 
156 	u32 dsiclk;	/* pll_clk / 2 */
157 };
158 
159 static inline struct tc358768_priv *dsi_host_to_tc358768(struct mipi_dsi_host
160 							 *host)
161 {
162 	return container_of(host, struct tc358768_priv, dsi_host);
163 }
164 
165 static inline struct tc358768_priv *bridge_to_tc358768(struct drm_bridge
166 						       *bridge)
167 {
168 	return container_of(bridge, struct tc358768_priv, bridge);
169 }
170 
171 static int tc358768_clear_error(struct tc358768_priv *priv)
172 {
173 	int ret = priv->error;
174 
175 	priv->error = 0;
176 	return ret;
177 }
178 
179 static void tc358768_write(struct tc358768_priv *priv, u32 reg, u32 val)
180 {
181 	/* work around https://gcc.gnu.org/bugzilla/show_bug.cgi?id=81715 */
182 	int tmpval = val;
183 	size_t count = 2;
184 
185 	if (priv->error)
186 		return;
187 
188 	/* 16-bit register? */
189 	if (reg < 0x100 || reg >= 0x600)
190 		count = 1;
191 
192 	priv->error = regmap_bulk_write(priv->regmap, reg, &tmpval, count);
193 }
194 
195 static void tc358768_read(struct tc358768_priv *priv, u32 reg, u32 *val)
196 {
197 	size_t count = 2;
198 
199 	if (priv->error)
200 		return;
201 
202 	/* 16-bit register? */
203 	if (reg < 0x100 || reg >= 0x600) {
204 		*val = 0;
205 		count = 1;
206 	}
207 
208 	priv->error = regmap_bulk_read(priv->regmap, reg, val, count);
209 }
210 
211 static void tc358768_update_bits(struct tc358768_priv *priv, u32 reg, u32 mask,
212 				 u32 val)
213 {
214 	u32 tmp, orig;
215 
216 	tc358768_read(priv, reg, &orig);
217 	tmp = orig & ~mask;
218 	tmp |= val & mask;
219 	if (tmp != orig)
220 		tc358768_write(priv, reg, tmp);
221 }
222 
223 static int tc358768_sw_reset(struct tc358768_priv *priv)
224 {
225 	/* Assert Reset */
226 	tc358768_write(priv, TC358768_SYSCTL, 1);
227 	/* Release Reset, Exit Sleep */
228 	tc358768_write(priv, TC358768_SYSCTL, 0);
229 
230 	return tc358768_clear_error(priv);
231 }
232 
233 static void tc358768_hw_enable(struct tc358768_priv *priv)
234 {
235 	int ret;
236 
237 	if (priv->enabled)
238 		return;
239 
240 	ret = clk_prepare_enable(priv->refclk);
241 	if (ret < 0)
242 		dev_err(priv->dev, "error enabling refclk (%d)\n", ret);
243 
244 	ret = regulator_bulk_enable(ARRAY_SIZE(priv->supplies), priv->supplies);
245 	if (ret < 0)
246 		dev_err(priv->dev, "error enabling regulators (%d)\n", ret);
247 
248 	if (priv->reset_gpio)
249 		usleep_range(200, 300);
250 
251 	/*
252 	 * The RESX is active low (GPIO_ACTIVE_LOW).
253 	 * DEASSERT (value = 0) the reset_gpio to enable the chip
254 	 */
255 	gpiod_set_value_cansleep(priv->reset_gpio, 0);
256 
257 	/* wait for encoder clocks to stabilize */
258 	usleep_range(1000, 2000);
259 
260 	priv->enabled = true;
261 }
262 
263 static void tc358768_hw_disable(struct tc358768_priv *priv)
264 {
265 	int ret;
266 
267 	if (!priv->enabled)
268 		return;
269 
270 	/*
271 	 * The RESX is active low (GPIO_ACTIVE_LOW).
272 	 * ASSERT (value = 1) the reset_gpio to disable the chip
273 	 */
274 	gpiod_set_value_cansleep(priv->reset_gpio, 1);
275 
276 	ret = regulator_bulk_disable(ARRAY_SIZE(priv->supplies),
277 				     priv->supplies);
278 	if (ret < 0)
279 		dev_err(priv->dev, "error disabling regulators (%d)\n", ret);
280 
281 	clk_disable_unprepare(priv->refclk);
282 
283 	priv->enabled = false;
284 }
285 
286 static u32 tc358768_pll_to_pclk(struct tc358768_priv *priv, u32 pll_clk)
287 {
288 	return (u32)div_u64((u64)pll_clk * priv->dsi_lanes, priv->pd_lines);
289 }
290 
291 static u32 tc358768_pclk_to_pll(struct tc358768_priv *priv, u32 pclk)
292 {
293 	return (u32)div_u64((u64)pclk * priv->pd_lines, priv->dsi_lanes);
294 }
295 
296 static int tc358768_calc_pll(struct tc358768_priv *priv,
297 			     const struct drm_display_mode *mode,
298 			     bool verify_only)
299 {
300 	static const u32 frs_limits[] = {
301 		1000000000,
302 		500000000,
303 		250000000,
304 		125000000,
305 		62500000
306 	};
307 	unsigned long refclk;
308 	u32 prd, target_pll, i, max_pll, min_pll;
309 	u32 frs, best_diff, best_pll, best_prd, best_fbd;
310 
311 	target_pll = tc358768_pclk_to_pll(priv, mode->clock * 1000);
312 
313 	/* pll_clk = RefClk * [(FBD + 1)/ (PRD + 1)] * [1 / (2^FRS)] */
314 
315 	for (i = 0; i < ARRAY_SIZE(frs_limits); i++)
316 		if (target_pll >= frs_limits[i])
317 			break;
318 
319 	if (i == ARRAY_SIZE(frs_limits) || i == 0)
320 		return -EINVAL;
321 
322 	frs = i - 1;
323 	max_pll = frs_limits[i - 1];
324 	min_pll = frs_limits[i];
325 
326 	refclk = clk_get_rate(priv->refclk);
327 
328 	best_diff = UINT_MAX;
329 	best_pll = 0;
330 	best_prd = 0;
331 	best_fbd = 0;
332 
333 	for (prd = 0; prd < 16; ++prd) {
334 		u32 divisor = (prd + 1) * (1 << frs);
335 		u32 fbd;
336 
337 		for (fbd = 0; fbd < 512; ++fbd) {
338 			u32 pll, diff;
339 
340 			pll = (u32)div_u64((u64)refclk * (fbd + 1), divisor);
341 
342 			if (pll >= max_pll || pll < min_pll)
343 				continue;
344 
345 			diff = max(pll, target_pll) - min(pll, target_pll);
346 
347 			if (diff < best_diff) {
348 				best_diff = diff;
349 				best_pll = pll;
350 				best_prd = prd;
351 				best_fbd = fbd;
352 
353 				if (best_diff == 0)
354 					goto found;
355 			}
356 		}
357 	}
358 
359 	if (best_diff == UINT_MAX) {
360 		dev_err(priv->dev, "could not find suitable PLL setup\n");
361 		return -EINVAL;
362 	}
363 
364 found:
365 	if (verify_only)
366 		return 0;
367 
368 	priv->fbd = best_fbd;
369 	priv->prd = best_prd;
370 	priv->frs = frs;
371 	priv->dsiclk = best_pll / 2;
372 
373 	return 0;
374 }
375 
376 static int tc358768_dsi_host_attach(struct mipi_dsi_host *host,
377 				    struct mipi_dsi_device *dev)
378 {
379 	struct tc358768_priv *priv = dsi_host_to_tc358768(host);
380 	struct drm_bridge *bridge;
381 	struct drm_panel *panel;
382 	struct device_node *ep;
383 	int ret;
384 
385 	if (dev->lanes > 4) {
386 		dev_err(priv->dev, "unsupported number of data lanes(%u)\n",
387 			dev->lanes);
388 		return -EINVAL;
389 	}
390 
391 	/*
392 	 * tc358768 supports both Video and Pulse mode, but the driver only
393 	 * implements Video (event) mode currently
394 	 */
395 	if (!(dev->mode_flags & MIPI_DSI_MODE_VIDEO)) {
396 		dev_err(priv->dev, "Only MIPI_DSI_MODE_VIDEO is supported\n");
397 		return -ENOTSUPP;
398 	}
399 
400 	/*
401 	 * tc358768 supports RGB888, RGB666, RGB666_PACKED and RGB565, but only
402 	 * RGB888 is verified.
403 	 */
404 	if (dev->format != MIPI_DSI_FMT_RGB888) {
405 		dev_warn(priv->dev, "Only MIPI_DSI_FMT_RGB888 tested!\n");
406 		return -ENOTSUPP;
407 	}
408 
409 	ret = drm_of_find_panel_or_bridge(host->dev->of_node, 1, 0, &panel,
410 					  &bridge);
411 	if (ret)
412 		return ret;
413 
414 	if (panel) {
415 		bridge = drm_panel_bridge_add_typed(panel,
416 						    DRM_MODE_CONNECTOR_DSI);
417 		if (IS_ERR(bridge))
418 			return PTR_ERR(bridge);
419 	}
420 
421 	priv->output.dev = dev;
422 	priv->output.bridge = bridge;
423 	priv->output.panel = panel;
424 
425 	priv->dsi_lanes = dev->lanes;
426 
427 	/* get input ep (port0/endpoint0) */
428 	ret = -EINVAL;
429 	ep = of_graph_get_endpoint_by_regs(host->dev->of_node, 0, 0);
430 	if (ep) {
431 		ret = of_property_read_u32(ep, "data-lines", &priv->pd_lines);
432 
433 		of_node_put(ep);
434 	}
435 
436 	if (ret)
437 		priv->pd_lines = mipi_dsi_pixel_format_to_bpp(dev->format);
438 
439 	drm_bridge_add(&priv->bridge);
440 
441 	return 0;
442 }
443 
444 static int tc358768_dsi_host_detach(struct mipi_dsi_host *host,
445 				    struct mipi_dsi_device *dev)
446 {
447 	struct tc358768_priv *priv = dsi_host_to_tc358768(host);
448 
449 	drm_bridge_remove(&priv->bridge);
450 	if (priv->output.panel)
451 		drm_panel_bridge_remove(priv->output.bridge);
452 
453 	return 0;
454 }
455 
456 static ssize_t tc358768_dsi_host_transfer(struct mipi_dsi_host *host,
457 					  const struct mipi_dsi_msg *msg)
458 {
459 	struct tc358768_priv *priv = dsi_host_to_tc358768(host);
460 	struct mipi_dsi_packet packet;
461 	int ret;
462 
463 	if (!priv->enabled) {
464 		dev_err(priv->dev, "Bridge is not enabled\n");
465 		return -ENODEV;
466 	}
467 
468 	if (msg->rx_len) {
469 		dev_warn(priv->dev, "MIPI rx is not supported\n");
470 		return -ENOTSUPP;
471 	}
472 
473 	if (msg->tx_len > 8) {
474 		dev_warn(priv->dev, "Maximum 8 byte MIPI tx is supported\n");
475 		return -ENOTSUPP;
476 	}
477 
478 	ret = mipi_dsi_create_packet(&packet, msg);
479 	if (ret)
480 		return ret;
481 
482 	if (mipi_dsi_packet_format_is_short(msg->type)) {
483 		tc358768_write(priv, TC358768_DSICMD_TYPE,
484 			       (0x10 << 8) | (packet.header[0] & 0x3f));
485 		tc358768_write(priv, TC358768_DSICMD_WC, 0);
486 		tc358768_write(priv, TC358768_DSICMD_WD0,
487 			       (packet.header[2] << 8) | packet.header[1]);
488 	} else {
489 		int i;
490 
491 		tc358768_write(priv, TC358768_DSICMD_TYPE,
492 			       (0x40 << 8) | (packet.header[0] & 0x3f));
493 		tc358768_write(priv, TC358768_DSICMD_WC, packet.payload_length);
494 		for (i = 0; i < packet.payload_length; i += 2) {
495 			u16 val = packet.payload[i];
496 
497 			if (i + 1 < packet.payload_length)
498 				val |= packet.payload[i + 1] << 8;
499 
500 			tc358768_write(priv, TC358768_DSICMD_WD0 + i, val);
501 		}
502 	}
503 
504 	/* start transfer */
505 	tc358768_write(priv, TC358768_DSICMD_TX, 1);
506 
507 	ret = tc358768_clear_error(priv);
508 	if (ret)
509 		dev_warn(priv->dev, "Software disable failed: %d\n", ret);
510 	else
511 		ret = packet.size;
512 
513 	return ret;
514 }
515 
516 static const struct mipi_dsi_host_ops tc358768_dsi_host_ops = {
517 	.attach = tc358768_dsi_host_attach,
518 	.detach = tc358768_dsi_host_detach,
519 	.transfer = tc358768_dsi_host_transfer,
520 };
521 
522 static int tc358768_bridge_attach(struct drm_bridge *bridge,
523 				  enum drm_bridge_attach_flags flags)
524 {
525 	struct tc358768_priv *priv = bridge_to_tc358768(bridge);
526 
527 	if (!drm_core_check_feature(bridge->dev, DRIVER_ATOMIC)) {
528 		dev_err(priv->dev, "needs atomic updates support\n");
529 		return -ENOTSUPP;
530 	}
531 
532 	return drm_bridge_attach(bridge->encoder, priv->output.bridge, bridge,
533 				 flags);
534 }
535 
536 static enum drm_mode_status
537 tc358768_bridge_mode_valid(struct drm_bridge *bridge,
538 			   const struct drm_display_info *info,
539 			   const struct drm_display_mode *mode)
540 {
541 	struct tc358768_priv *priv = bridge_to_tc358768(bridge);
542 
543 	if (tc358768_calc_pll(priv, mode, true))
544 		return MODE_CLOCK_RANGE;
545 
546 	return MODE_OK;
547 }
548 
549 static void tc358768_bridge_disable(struct drm_bridge *bridge)
550 {
551 	struct tc358768_priv *priv = bridge_to_tc358768(bridge);
552 	int ret;
553 
554 	/* set FrmStop */
555 	tc358768_update_bits(priv, TC358768_PP_MISC, BIT(15), BIT(15));
556 
557 	/* wait at least for one frame */
558 	msleep(50);
559 
560 	/* clear PP_en */
561 	tc358768_update_bits(priv, TC358768_CONFCTL, BIT(6), 0);
562 
563 	/* set RstPtr */
564 	tc358768_update_bits(priv, TC358768_PP_MISC, BIT(14), BIT(14));
565 
566 	ret = tc358768_clear_error(priv);
567 	if (ret)
568 		dev_warn(priv->dev, "Software disable failed: %d\n", ret);
569 }
570 
571 static void tc358768_bridge_post_disable(struct drm_bridge *bridge)
572 {
573 	struct tc358768_priv *priv = bridge_to_tc358768(bridge);
574 
575 	tc358768_hw_disable(priv);
576 }
577 
578 static int tc358768_setup_pll(struct tc358768_priv *priv,
579 			      const struct drm_display_mode *mode)
580 {
581 	u32 fbd, prd, frs;
582 	int ret;
583 
584 	ret = tc358768_calc_pll(priv, mode, false);
585 	if (ret) {
586 		dev_err(priv->dev, "PLL calculation failed: %d\n", ret);
587 		return ret;
588 	}
589 
590 	fbd = priv->fbd;
591 	prd = priv->prd;
592 	frs = priv->frs;
593 
594 	dev_dbg(priv->dev, "PLL: refclk %lu, fbd %u, prd %u, frs %u\n",
595 		clk_get_rate(priv->refclk), fbd, prd, frs);
596 	dev_dbg(priv->dev, "PLL: pll_clk: %u, DSIClk %u, DSIByteClk %u\n",
597 		priv->dsiclk * 2, priv->dsiclk, priv->dsiclk / 4);
598 	dev_dbg(priv->dev, "PLL: pclk %u (panel: %u)\n",
599 		tc358768_pll_to_pclk(priv, priv->dsiclk * 2),
600 		mode->clock * 1000);
601 
602 	/* PRD[15:12] FBD[8:0] */
603 	tc358768_write(priv, TC358768_PLLCTL0, (prd << 12) | fbd);
604 
605 	/* FRS[11:10] LBWS[9:8] CKEN[4] RESETB[1] EN[0] */
606 	tc358768_write(priv, TC358768_PLLCTL1,
607 		       (frs << 10) | (0x2 << 8) | BIT(1) | BIT(0));
608 
609 	/* wait for lock */
610 	usleep_range(1000, 2000);
611 
612 	/* FRS[11:10] LBWS[9:8] CKEN[4] PLL_CKEN[4] RESETB[1] EN[0] */
613 	tc358768_write(priv, TC358768_PLLCTL1,
614 		       (frs << 10) | (0x2 << 8) | BIT(4) | BIT(1) | BIT(0));
615 
616 	return tc358768_clear_error(priv);
617 }
618 
619 #define TC358768_PRECISION	1000
620 static u32 tc358768_ns_to_cnt(u32 ns, u32 period_nsk)
621 {
622 	return (ns * TC358768_PRECISION + period_nsk) / period_nsk;
623 }
624 
625 static u32 tc358768_to_ns(u32 nsk)
626 {
627 	return (nsk / TC358768_PRECISION);
628 }
629 
630 static void tc358768_bridge_pre_enable(struct drm_bridge *bridge)
631 {
632 	struct tc358768_priv *priv = bridge_to_tc358768(bridge);
633 	struct mipi_dsi_device *dsi_dev = priv->output.dev;
634 	unsigned long mode_flags = dsi_dev->mode_flags;
635 	u32 val, val2, lptxcnt, hact, data_type;
636 	const struct drm_display_mode *mode;
637 	u32 dsibclk_nsk, dsiclk_nsk, ui_nsk, phy_delay_nsk;
638 	u32 dsiclk, dsibclk, video_start;
639 	const u32 internal_delay = 40;
640 	int ret, i;
641 
642 	if (mode_flags & MIPI_DSI_CLOCK_NON_CONTINUOUS) {
643 		dev_warn_once(priv->dev, "Non-continuous mode unimplemented, falling back to continuous\n");
644 		mode_flags &= ~MIPI_DSI_CLOCK_NON_CONTINUOUS;
645 	}
646 
647 	tc358768_hw_enable(priv);
648 
649 	ret = tc358768_sw_reset(priv);
650 	if (ret) {
651 		dev_err(priv->dev, "Software reset failed: %d\n", ret);
652 		tc358768_hw_disable(priv);
653 		return;
654 	}
655 
656 	mode = &bridge->encoder->crtc->state->adjusted_mode;
657 	ret = tc358768_setup_pll(priv, mode);
658 	if (ret) {
659 		dev_err(priv->dev, "PLL setup failed: %d\n", ret);
660 		tc358768_hw_disable(priv);
661 		return;
662 	}
663 
664 	dsiclk = priv->dsiclk;
665 	dsibclk = dsiclk / 4;
666 
667 	/* Data Format Control Register */
668 	val = BIT(2) | BIT(1) | BIT(0); /* rdswap_en | dsitx_en | txdt_en */
669 	switch (dsi_dev->format) {
670 	case MIPI_DSI_FMT_RGB888:
671 		val |= (0x3 << 4);
672 		hact = mode->hdisplay * 3;
673 		video_start = (mode->htotal - mode->hsync_start) * 3;
674 		data_type = MIPI_DSI_PACKED_PIXEL_STREAM_24;
675 		break;
676 	case MIPI_DSI_FMT_RGB666:
677 		val |= (0x4 << 4);
678 		hact = mode->hdisplay * 3;
679 		video_start = (mode->htotal - mode->hsync_start) * 3;
680 		data_type = MIPI_DSI_PACKED_PIXEL_STREAM_18;
681 		break;
682 
683 	case MIPI_DSI_FMT_RGB666_PACKED:
684 		val |= (0x4 << 4) | BIT(3);
685 		hact = mode->hdisplay * 18 / 8;
686 		video_start = (mode->htotal - mode->hsync_start) * 18 / 8;
687 		data_type = MIPI_DSI_PIXEL_STREAM_3BYTE_18;
688 		break;
689 
690 	case MIPI_DSI_FMT_RGB565:
691 		val |= (0x5 << 4);
692 		hact = mode->hdisplay * 2;
693 		video_start = (mode->htotal - mode->hsync_start) * 2;
694 		data_type = MIPI_DSI_PACKED_PIXEL_STREAM_16;
695 		break;
696 	default:
697 		dev_err(priv->dev, "Invalid data format (%u)\n",
698 			dsi_dev->format);
699 		tc358768_hw_disable(priv);
700 		return;
701 	}
702 
703 	/* VSDly[9:0] */
704 	video_start = max(video_start, internal_delay + 1) - internal_delay;
705 	tc358768_write(priv, TC358768_VSDLY, video_start);
706 
707 	tc358768_write(priv, TC358768_DATAFMT, val);
708 	tc358768_write(priv, TC358768_DSITX_DT, data_type);
709 
710 	/* Enable D-PHY (HiZ->LP11) */
711 	tc358768_write(priv, TC358768_CLW_CNTRL, 0x0000);
712 	/* Enable lanes */
713 	for (i = 0; i < dsi_dev->lanes; i++)
714 		tc358768_write(priv, TC358768_D0W_CNTRL + i * 4, 0x0000);
715 
716 	/* DSI Timings */
717 	dsibclk_nsk = (u32)div_u64((u64)1000000000 * TC358768_PRECISION,
718 				  dsibclk);
719 	dsiclk_nsk = (u32)div_u64((u64)1000000000 * TC358768_PRECISION, dsiclk);
720 	ui_nsk = dsiclk_nsk / 2;
721 	phy_delay_nsk = dsibclk_nsk + 2 * dsiclk_nsk;
722 	dev_dbg(priv->dev, "dsiclk_nsk: %u\n", dsiclk_nsk);
723 	dev_dbg(priv->dev, "ui_nsk: %u\n", ui_nsk);
724 	dev_dbg(priv->dev, "dsibclk_nsk: %u\n", dsibclk_nsk);
725 	dev_dbg(priv->dev, "phy_delay_nsk: %u\n", phy_delay_nsk);
726 
727 	/* LP11 > 100us for D-PHY Rx Init */
728 	val = tc358768_ns_to_cnt(100 * 1000, dsibclk_nsk) - 1;
729 	dev_dbg(priv->dev, "LINEINITCNT: 0x%x\n", val);
730 	tc358768_write(priv, TC358768_LINEINITCNT, val);
731 
732 	/* LPTimeCnt > 50ns */
733 	val = tc358768_ns_to_cnt(50, dsibclk_nsk) - 1;
734 	lptxcnt = val;
735 	dev_dbg(priv->dev, "LPTXTIMECNT: 0x%x\n", val);
736 	tc358768_write(priv, TC358768_LPTXTIMECNT, val);
737 
738 	/* 38ns < TCLK_PREPARE < 95ns */
739 	val = tc358768_ns_to_cnt(65, dsibclk_nsk) - 1;
740 	/* TCLK_PREPARE > 300ns */
741 	val2 = tc358768_ns_to_cnt(300 + tc358768_to_ns(3 * ui_nsk),
742 				  dsibclk_nsk);
743 	val |= (val2 - tc358768_to_ns(phy_delay_nsk - dsibclk_nsk)) << 8;
744 	dev_dbg(priv->dev, "TCLK_HEADERCNT: 0x%x\n", val);
745 	tc358768_write(priv, TC358768_TCLK_HEADERCNT, val);
746 
747 	/* TCLK_TRAIL > 60ns + 3*UI */
748 	val = 60 + tc358768_to_ns(3 * ui_nsk);
749 	val = tc358768_ns_to_cnt(val, dsibclk_nsk) - 5;
750 	dev_dbg(priv->dev, "TCLK_TRAILCNT: 0x%x\n", val);
751 	tc358768_write(priv, TC358768_TCLK_TRAILCNT, val);
752 
753 	/* 40ns + 4*UI < THS_PREPARE < 85ns + 6*UI */
754 	val = 50 + tc358768_to_ns(4 * ui_nsk);
755 	val = tc358768_ns_to_cnt(val, dsibclk_nsk) - 1;
756 	/* THS_ZERO > 145ns + 10*UI */
757 	val2 = tc358768_ns_to_cnt(145 - tc358768_to_ns(ui_nsk), dsibclk_nsk);
758 	val |= (val2 - tc358768_to_ns(phy_delay_nsk)) << 8;
759 	dev_dbg(priv->dev, "THS_HEADERCNT: 0x%x\n", val);
760 	tc358768_write(priv, TC358768_THS_HEADERCNT, val);
761 
762 	/* TWAKEUP > 1ms in lptxcnt steps */
763 	val = tc358768_ns_to_cnt(1020000, dsibclk_nsk);
764 	val = val / (lptxcnt + 1) - 1;
765 	dev_dbg(priv->dev, "TWAKEUP: 0x%x\n", val);
766 	tc358768_write(priv, TC358768_TWAKEUP, val);
767 
768 	/* TCLK_POSTCNT > 60ns + 52*UI */
769 	val = tc358768_ns_to_cnt(60 + tc358768_to_ns(52 * ui_nsk),
770 				 dsibclk_nsk) - 3;
771 	dev_dbg(priv->dev, "TCLK_POSTCNT: 0x%x\n", val);
772 	tc358768_write(priv, TC358768_TCLK_POSTCNT, val);
773 
774 	/* 60ns + 4*UI < THS_PREPARE < 105ns + 12*UI */
775 	val = tc358768_ns_to_cnt(60 + tc358768_to_ns(15 * ui_nsk),
776 				 dsibclk_nsk) - 5;
777 	dev_dbg(priv->dev, "THS_TRAILCNT: 0x%x\n", val);
778 	tc358768_write(priv, TC358768_THS_TRAILCNT, val);
779 
780 	val = BIT(0);
781 	for (i = 0; i < dsi_dev->lanes; i++)
782 		val |= BIT(i + 1);
783 	tc358768_write(priv, TC358768_HSTXVREGEN, val);
784 
785 	if (!(mode_flags & MIPI_DSI_CLOCK_NON_CONTINUOUS))
786 		tc358768_write(priv, TC358768_TXOPTIONCNTRL, 0x1);
787 
788 	/* TXTAGOCNT[26:16] RXTASURECNT[10:0] */
789 	val = tc358768_to_ns((lptxcnt + 1) * dsibclk_nsk * 4);
790 	val = tc358768_ns_to_cnt(val, dsibclk_nsk) - 1;
791 	val2 = tc358768_ns_to_cnt(tc358768_to_ns((lptxcnt + 1) * dsibclk_nsk),
792 				  dsibclk_nsk) - 2;
793 	val = val << 16 | val2;
794 	dev_dbg(priv->dev, "BTACNTRL1: 0x%x\n", val);
795 	tc358768_write(priv, TC358768_BTACNTRL1, val);
796 
797 	/* START[0] */
798 	tc358768_write(priv, TC358768_STARTCNTRL, 1);
799 
800 	if (dsi_dev->mode_flags & MIPI_DSI_MODE_VIDEO_SYNC_PULSE) {
801 		/* Set pulse mode */
802 		tc358768_write(priv, TC358768_DSI_EVENT, 0);
803 
804 		/* vact */
805 		tc358768_write(priv, TC358768_DSI_VACT, mode->vdisplay);
806 
807 		/* vsw */
808 		tc358768_write(priv, TC358768_DSI_VSW,
809 			       mode->vsync_end - mode->vsync_start);
810 		/* vbp */
811 		tc358768_write(priv, TC358768_DSI_VBPR,
812 			       mode->vtotal - mode->vsync_end);
813 
814 		/* hsw * byteclk * ndl / pclk */
815 		val = (u32)div_u64((mode->hsync_end - mode->hsync_start) *
816 				   ((u64)priv->dsiclk / 4) * priv->dsi_lanes,
817 				   mode->clock * 1000);
818 		tc358768_write(priv, TC358768_DSI_HSW, val);
819 
820 		/* hbp * byteclk * ndl / pclk */
821 		val = (u32)div_u64((mode->htotal - mode->hsync_end) *
822 				   ((u64)priv->dsiclk / 4) * priv->dsi_lanes,
823 				   mode->clock * 1000);
824 		tc358768_write(priv, TC358768_DSI_HBPR, val);
825 	} else {
826 		/* Set event mode */
827 		tc358768_write(priv, TC358768_DSI_EVENT, 1);
828 
829 		/* vact */
830 		tc358768_write(priv, TC358768_DSI_VACT, mode->vdisplay);
831 
832 		/* vsw (+ vbp) */
833 		tc358768_write(priv, TC358768_DSI_VSW,
834 			       mode->vtotal - mode->vsync_start);
835 		/* vbp (not used in event mode) */
836 		tc358768_write(priv, TC358768_DSI_VBPR, 0);
837 
838 		/* (hsw + hbp) * byteclk * ndl / pclk */
839 		val = (u32)div_u64((mode->htotal - mode->hsync_start) *
840 				   ((u64)priv->dsiclk / 4) * priv->dsi_lanes,
841 				   mode->clock * 1000);
842 		tc358768_write(priv, TC358768_DSI_HSW, val);
843 
844 		/* hbp (not used in event mode) */
845 		tc358768_write(priv, TC358768_DSI_HBPR, 0);
846 	}
847 
848 	/* hact (bytes) */
849 	tc358768_write(priv, TC358768_DSI_HACT, hact);
850 
851 	/* VSYNC polarity */
852 	if (!(mode->flags & DRM_MODE_FLAG_NVSYNC))
853 		tc358768_update_bits(priv, TC358768_CONFCTL, BIT(5), BIT(5));
854 	/* HSYNC polarity */
855 	if (mode->flags & DRM_MODE_FLAG_PHSYNC)
856 		tc358768_update_bits(priv, TC358768_PP_MISC, BIT(0), BIT(0));
857 
858 	/* Start DSI Tx */
859 	tc358768_write(priv, TC358768_DSI_START, 0x1);
860 
861 	/* Configure DSI_Control register */
862 	val = TC358768_DSI_CONFW_MODE_CLR | TC358768_DSI_CONFW_ADDR_DSI_CONTROL;
863 	val |= TC358768_DSI_CONTROL_TXMD | TC358768_DSI_CONTROL_HSCKMD |
864 	       0x3 << 1 | TC358768_DSI_CONTROL_EOTDIS;
865 	tc358768_write(priv, TC358768_DSI_CONFW, val);
866 
867 	val = TC358768_DSI_CONFW_MODE_SET | TC358768_DSI_CONFW_ADDR_DSI_CONTROL;
868 	val |= (dsi_dev->lanes - 1) << 1;
869 
870 	if (!(dsi_dev->mode_flags & MIPI_DSI_MODE_LPM))
871 		val |= TC358768_DSI_CONTROL_TXMD;
872 
873 	if (!(mode_flags & MIPI_DSI_CLOCK_NON_CONTINUOUS))
874 		val |= TC358768_DSI_CONTROL_HSCKMD;
875 
876 	if (dsi_dev->mode_flags & MIPI_DSI_MODE_NO_EOT_PACKET)
877 		val |= TC358768_DSI_CONTROL_EOTDIS;
878 
879 	tc358768_write(priv, TC358768_DSI_CONFW, val);
880 
881 	val = TC358768_DSI_CONFW_MODE_CLR | TC358768_DSI_CONFW_ADDR_DSI_CONTROL;
882 	val |= TC358768_DSI_CONTROL_DIS_MODE; /* DSI mode */
883 	tc358768_write(priv, TC358768_DSI_CONFW, val);
884 
885 	ret = tc358768_clear_error(priv);
886 	if (ret) {
887 		dev_err(priv->dev, "Bridge pre_enable failed: %d\n", ret);
888 		tc358768_bridge_disable(bridge);
889 		tc358768_bridge_post_disable(bridge);
890 	}
891 }
892 
893 static void tc358768_bridge_enable(struct drm_bridge *bridge)
894 {
895 	struct tc358768_priv *priv = bridge_to_tc358768(bridge);
896 	int ret;
897 
898 	if (!priv->enabled) {
899 		dev_err(priv->dev, "Bridge is not enabled\n");
900 		return;
901 	}
902 
903 	/* clear FrmStop and RstPtr */
904 	tc358768_update_bits(priv, TC358768_PP_MISC, 0x3 << 14, 0);
905 
906 	/* set PP_en */
907 	tc358768_update_bits(priv, TC358768_CONFCTL, BIT(6), BIT(6));
908 
909 	ret = tc358768_clear_error(priv);
910 	if (ret) {
911 		dev_err(priv->dev, "Bridge enable failed: %d\n", ret);
912 		tc358768_bridge_disable(bridge);
913 		tc358768_bridge_post_disable(bridge);
914 	}
915 }
916 
917 static const struct drm_bridge_funcs tc358768_bridge_funcs = {
918 	.attach = tc358768_bridge_attach,
919 	.mode_valid = tc358768_bridge_mode_valid,
920 	.pre_enable = tc358768_bridge_pre_enable,
921 	.enable = tc358768_bridge_enable,
922 	.disable = tc358768_bridge_disable,
923 	.post_disable = tc358768_bridge_post_disable,
924 };
925 
926 static const struct drm_bridge_timings default_tc358768_timings = {
927 	.input_bus_flags = DRM_BUS_FLAG_PIXDATA_SAMPLE_POSEDGE
928 		 | DRM_BUS_FLAG_SYNC_SAMPLE_NEGEDGE
929 		 | DRM_BUS_FLAG_DE_HIGH,
930 };
931 
932 static bool tc358768_is_reserved_reg(unsigned int reg)
933 {
934 	switch (reg) {
935 	case 0x114 ... 0x13f:
936 	case 0x200:
937 	case 0x20c:
938 	case 0x400 ... 0x408:
939 	case 0x41c ... 0x42f:
940 		return true;
941 	default:
942 		return false;
943 	}
944 }
945 
946 static bool tc358768_writeable_reg(struct device *dev, unsigned int reg)
947 {
948 	if (tc358768_is_reserved_reg(reg))
949 		return false;
950 
951 	switch (reg) {
952 	case TC358768_CHIPID:
953 	case TC358768_FIFOSTATUS:
954 	case TC358768_DSITXSTATUS ... (TC358768_DSITXSTATUS + 2):
955 	case TC358768_DSI_CONTROL ... (TC358768_DSI_INT_ENA + 2):
956 	case TC358768_DSICMD_RDFIFO ... (TC358768_DSI_ERR_HALT + 2):
957 		return false;
958 	default:
959 		return true;
960 	}
961 }
962 
963 static bool tc358768_readable_reg(struct device *dev, unsigned int reg)
964 {
965 	if (tc358768_is_reserved_reg(reg))
966 		return false;
967 
968 	switch (reg) {
969 	case TC358768_STARTCNTRL:
970 	case TC358768_DSI_CONFW ... (TC358768_DSI_CONFW + 2):
971 	case TC358768_DSI_INT_CLR ... (TC358768_DSI_INT_CLR + 2):
972 	case TC358768_DSI_START ... (TC358768_DSI_START + 2):
973 	case TC358768_DBG_DATA:
974 		return false;
975 	default:
976 		return true;
977 	}
978 }
979 
980 static const struct regmap_config tc358768_regmap_config = {
981 	.name = "tc358768",
982 	.reg_bits = 16,
983 	.val_bits = 16,
984 	.max_register = TC358768_DSI_HACT,
985 	.cache_type = REGCACHE_NONE,
986 	.writeable_reg = tc358768_writeable_reg,
987 	.readable_reg = tc358768_readable_reg,
988 	.reg_format_endian = REGMAP_ENDIAN_BIG,
989 	.val_format_endian = REGMAP_ENDIAN_BIG,
990 };
991 
992 static const struct i2c_device_id tc358768_i2c_ids[] = {
993 	{ "tc358768", 0 },
994 	{ "tc358778", 0 },
995 	{ }
996 };
997 MODULE_DEVICE_TABLE(i2c, tc358768_i2c_ids);
998 
999 static const struct of_device_id tc358768_of_ids[] = {
1000 	{ .compatible = "toshiba,tc358768", },
1001 	{ .compatible = "toshiba,tc358778", },
1002 	{ }
1003 };
1004 MODULE_DEVICE_TABLE(of, tc358768_of_ids);
1005 
1006 static int tc358768_get_regulators(struct tc358768_priv *priv)
1007 {
1008 	int i, ret;
1009 
1010 	for (i = 0; i < ARRAY_SIZE(priv->supplies); ++i)
1011 		priv->supplies[i].supply = tc358768_supplies[i];
1012 
1013 	ret = devm_regulator_bulk_get(priv->dev, ARRAY_SIZE(priv->supplies),
1014 				      priv->supplies);
1015 	if (ret < 0)
1016 		dev_err(priv->dev, "failed to get regulators: %d\n", ret);
1017 
1018 	return ret;
1019 }
1020 
1021 static int tc358768_i2c_probe(struct i2c_client *client,
1022 			      const struct i2c_device_id *id)
1023 {
1024 	struct tc358768_priv *priv;
1025 	struct device *dev = &client->dev;
1026 	struct device_node *np = dev->of_node;
1027 	int ret;
1028 
1029 	if (!np)
1030 		return -ENODEV;
1031 
1032 	priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
1033 	if (!priv)
1034 		return -ENOMEM;
1035 
1036 	dev_set_drvdata(dev, priv);
1037 	priv->dev = dev;
1038 
1039 	ret = tc358768_get_regulators(priv);
1040 	if (ret)
1041 		return ret;
1042 
1043 	priv->refclk = devm_clk_get(dev, "refclk");
1044 	if (IS_ERR(priv->refclk))
1045 		return PTR_ERR(priv->refclk);
1046 
1047 	/*
1048 	 * RESX is low active, to disable tc358768 initially (keep in reset)
1049 	 * the gpio line must be LOW. This is the ASSERTED state of
1050 	 * GPIO_ACTIVE_LOW (GPIOD_OUT_HIGH == ASSERTED).
1051 	 */
1052 	priv->reset_gpio  = devm_gpiod_get_optional(dev, "reset",
1053 						    GPIOD_OUT_HIGH);
1054 	if (IS_ERR(priv->reset_gpio))
1055 		return PTR_ERR(priv->reset_gpio);
1056 
1057 	priv->regmap = devm_regmap_init_i2c(client, &tc358768_regmap_config);
1058 	if (IS_ERR(priv->regmap)) {
1059 		dev_err(dev, "Failed to init regmap\n");
1060 		return PTR_ERR(priv->regmap);
1061 	}
1062 
1063 	priv->dsi_host.dev = dev;
1064 	priv->dsi_host.ops = &tc358768_dsi_host_ops;
1065 
1066 	priv->bridge.funcs = &tc358768_bridge_funcs;
1067 	priv->bridge.timings = &default_tc358768_timings;
1068 	priv->bridge.of_node = np;
1069 
1070 	i2c_set_clientdata(client, priv);
1071 
1072 	return mipi_dsi_host_register(&priv->dsi_host);
1073 }
1074 
1075 static int tc358768_i2c_remove(struct i2c_client *client)
1076 {
1077 	struct tc358768_priv *priv = i2c_get_clientdata(client);
1078 
1079 	mipi_dsi_host_unregister(&priv->dsi_host);
1080 
1081 	return 0;
1082 }
1083 
1084 static struct i2c_driver tc358768_driver = {
1085 	.driver = {
1086 		.name = "tc358768",
1087 		.of_match_table = tc358768_of_ids,
1088 	},
1089 	.id_table = tc358768_i2c_ids,
1090 	.probe = tc358768_i2c_probe,
1091 	.remove	= tc358768_i2c_remove,
1092 };
1093 module_i2c_driver(tc358768_driver);
1094 
1095 MODULE_AUTHOR("Peter Ujfalusi <peter.ujfalusi@ti.com>");
1096 MODULE_DESCRIPTION("TC358768AXBG/TC358778XBG DSI bridge");
1097 MODULE_LICENSE("GPL v2");
1098